The Vanishing — Insect Extinction Is Another Canary in the Coal Mine

October 31, 2017 |
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Story at-a-glance

A 76 percent decline in flying insects was revealed over a period of 27 years in Germany

The researchers observed insects in nature preserves that are meant to protect ecosystem functioning and biodiversity, making the decline even more alarming

Ninety-four percent of the protected areas included in the study were enclosed by agricultural areas, and increasing use of pesticides was named as a possible cause for the decline

It’s estimated that 80 percent of wild plants depend on insects for pollination, and 60 percent of birds depend on them for food

By Dr. Mercola

If you've ever gone on a road trip, you probably have distinct memories of bugs flying at, and smashing on, your windshield — along with the inevitable cleanup the mess necessitated afterward. If you think about it for a minute, though, you may realize that it's been awhile since your windshield was covered with insects.

This may initially seem like a good thing, but this occurrence, dubbed the "windshield phenomenon" by entomologists,1 is an ominous warning — a canary in the coalmine that the environment is in grave danger.

"I'm a very data-driven person," Scott Black, executive director of the Xerces Society for Invertebrate Conservation in Portland, Oregon, told Science. "But it is a visceral reaction when you realize you don't see that mess anymore."2 It's also not all in your head. Insects are vanishing right before our eyes, at a rate that's at once sobering and alarming.

Seventy-Six Percent of Flying Insects Have Disappeared in the Last 27 Years

Declines in certain insect groups like bees, butterflies and even moths have been apparent for some time, according to researchers of a recent study published in PLOS One.3 However, their study looked at total flying insect biomass over a period of 27 years in 63 protected areas in Germany to assess the bigger picture. Using malaise traps, which are large, tent-like traps used for catching flying insects, the researchers set out to estimate trends in the number of flying insects in the region between 1989 and 2016.

A 76 percent decline was revealed, seasonally, while a midsummer decline of 82 percent in flying insect biomass was also recorded. The declines occurred regardless of habitat type and could not be explained solely by changes in weather, land use or varying habitat characteristics. The researchers noted:4

"Loss of insect diversity and abundance is expected to provoke cascading effects on food webs and to jeopardize ecosystem services … This yet unrecognized loss of insect biomass must be taken into account in evaluating declines in abundance of species depending on insects as a food source, and ecosystem functioning … "

The ramifications of disappearing insects should not be taken lightly. It's estimated that 80 percent of wild plants depend on insects for pollination, and 60 percent of birds depend on them for food. Further, the "ecosystem services" provided by insects as a whole is estimated at $57 billion annually in the U.S. alone, the researchers noted, so "[c]learly, preserving insect abundance and diversity should constitute a prime conservation priority."5

While increasing attention has been given to declines in bees and butterflies, the data suggest that "it is not only the vulnerable species, but the flying insect community as a whole, that has been decimated over the last few decades."

The researchers described the significant decline as "alarming," made even more so because the traps were placed in nature preserves that are meant to protect ecosystem functioning and biodiversity. Still, nearly all (94 percent) of the protected areas included in the study were enclosed by agricultural areas, giving clues as to why so many insects may be disappearing.

'Agricultural Intensification' May Be Killing Off Insects at an Alarming Rate

After observing the massive decline in flying insects in under 30 years, the researchers then began looking into potential driving mechanisms. Landscape and climate changes were not strongly associated with the declines, according to their analysis, so they suggested other "large-scale factors," like agricultural intensification, may be involved:6

"Agricultural intensification (e.g., pesticide usage, year-round tillage, increased use of fertilizers and frequency of agronomic measures) that we could not incorporate in our analyses, may form a plausible cause … Part of the explanation could therefore be that the protected areas (serving as insect sources) are affected and drained by the agricultural fields in the broader surroundings (serving as sinks or even as ecological traps).

Increased agricultural intensification may have aggravated this reduction in insect abundance in the protected areas over the last few decades … Agricultural intensification, including the disappearance of field margins and new crop protection methods has been associated with an overall decline of biodiversity in plants, insects, birds and other species in the current landscape."

Indeed, while the observational study wasn't set up to determine causes for the insect decline, the increasing use of agricultural chemicals is a prime suspect, one that's been implicated in insect losses before. For instance, numbers of Monarch butterflies have decreased by 90 percent since 1996. As usage of glyphosate (the active ingredient in Monsanto's Roundup herbicide) has skyrocketed, milkweed, which is the only plant on which the adult monarch will lay its eggs, has plummeted.

In 2013, it was estimated that just 1 percent of the common milkweed present in 1999 remained in corn and soybean fields and, tragically, while milkweed is not harmed by many herbicides, it is easily killed by glyphosate.7 A 2017 study published in the journal Ecography further noted a strong connection between large-scale Monarch deaths and glyphosate application.8,9

Neonicotinoid pesticides, which are widely used in intensive agricultural operations, have been implicated in the decline of bees, particularly in commercially bred species like honeybees and bumblebees, although wild foraging bees may be negatively affected also.10 Neonicotinoids are the most widely used insecticides on the planet.

As systemic pesticides, the chemicals are typically applied to seeds before they're planted, then taken up by plants as they grow, contaminating flowers, nectar and pollen. "Neonicotinoids are suspected to pose an unacceptable risk to bees, partly because of their systemic uptake in plants, and the European Union has therefore introduced a moratorium on three neonicotinoids as seed coatings in flowering crops that attract bees," a study published in Nature revealed in 2015.11

Separate research published in the journal Nature also suggests that combined exposure to neonicotinoid pesticides and parasites may alter queen bees' physiology and survival, thereby potentially destroying the whole hive.12 Butterflies are also being affected.

Researchers from the University of Nevada tracked 67 butterfly species at four locations for at least 20 years.13 At each site, declines in the number of butterfly species were most closely linked to increased used of neonicotinoids, even more so than other potential factors in butterfly declines, like land development.14

Applying the chemicals to plant seeds, rather than spraying them across a field, was supposed to reduce the effects on nontarget insects, but research published in PeerJ found both types of insecticides are equally damaging.15 The study revealed that the use of neonicotinoid insecticides in North American and European farming systems led to a 10 percent to 20 percent decline in predatory insects like tiger beetles, which is similar to those caused by "broadcast applications" of pyrethroid insecticides.

Like pollinators, predatory insects also have an important role in the ecosystem, contributing "billions of dollars a year to agriculture through the elimination of crop pest insects," study author Margaret Douglas, postdoctoral researcher in entomology, Penn State, said in a news release.16

Another predatory insect, parasitoid wasps, are also at risk from the chemicals. Research revealed that exposure to just 1 nanogram of the neonicotinoid imidacloproid, while not enough to kill the insect, reduced mating rates by up to 80 percent, which is essentially the same thing on a specieswide level.17

What Happens If Honey Bees, Other Flying Insects Disappear?

It's extremely important that steps are taken to protect bees, butterflies and other pollinators. These creatures are necessary to help 80 percent of flowering plants reproduce and are involved in the production of 1 out of every 3 bites of food. A sampling of the produce that would disappear without bees is below.18

There are ramifications beyond pollinators as well. Scott Black, executive director of the Portland, Oregon-based environmental group Xerces Society, told The Washington Post, "If you like to eat nutritious fruits and vegetables, you should thank an insect. If you like salmon, you can thank a tiny fly that the salmon eat when they're young … The whole fabric of our planet is built on plants and insects and the relationship between the two."19

Reducing Pesticide Usage Is Key

The application of chemicals in agriculture is now so commonplace that it seems necessary, but pesticide usage can be cut — without harming yields. According to an investigation by the U.S. Environmental Protection Agency (EPA), treating soybean seeds with neonicotinoids provides no significant financial or agricultural benefits for farmers.20 The researchers also noted there are several other foliar insecticides available that can combat pests as effectively as neonicotinoid seed treatments, with fewer risks.

Other studies suggest reducing the use of pesticides may actually reduce crop losses.21 The reason for this is because neonic-coated seeds harm beneficial insects that help kill pests naturally,22 thereby making any infestation far worse than it needs to be. According to other research, ecologically-based farming that helps kill soybean aphids without pesticides could save farmers in four states (Iowa, Michigan, Minnesota and Wisconsin) nearly $240 million in losses each year.23

There's much work to be done, as despite such findings, farmers have very limited ability to avoid neonic-treated seeds. Still, positive changes are being made by some farmers. John Tooker, associate professor of entomology, Penn State, who was involved in the study that found neonicotinoids are harming predatory insects, noted that the use of integrated pest management (IPM) is also essential.

A 2015 study found that IPM techniques reduced pesticide use while boosting crop yields in a meta-analysis of 85 sites in 24 countries.24 Some were even able to eliminate pesticide use entirely using techniques such as crop rotation and pheromone traps to capture insect pests. Tooker said in a news release:25

"Substantial research exists supporting the value of IPM for pest control … It is the best chance we have of conserving beneficial insect species while maintaining productivity in our agricultural systems."

It's now common knowledge that deforestation leading to the tragic loss of vast swatches of rainforest is devastating the environment. Lesser known is the fact that U.S. prairies are equally as diverse and important to the ecosystem as rainforests; they're also similarly threatened.

Since the early 1800s, grasslands in North America have decreased by 79 percent — and in some areas by 99.9 percent,26 largely to plant vast swatches of chemically intensive genetically engineered (GE) corn and soy. A report by the U.S. Geological Survey explained, in part, why this is so tragic:27

"Grasslands rank among the most biologically productive of all communities. Their high productivity stems from high retention of nutrients, efficient biological recycling, and a structure that provides for a vast array of animal and plant life …

Grasslands also contribute immense value to watersheds and provide forage and habitat for large numbers of domestic and wild animals. Nevertheless, current levels of erosion in North America exceed the prairie soil's capacity to tolerate sediment and nutrient loss, thus threatening a resource essential to sustain future generations."

Unfortunately, a two-crop planting cycle of GE corn and soybeans, along with CAFOs (concentrated animal feeding operations) that raise one type of meat, has become the dominant model in the Midwest, thanks to the federal farm policy that subsidizes these crops, with devastating consequences to human health and the environment. Choosing grass fed products like grass fed beef and bison over those raised in CAFOs is a solution that we can all take part in.

Consumer demand for more humane, environmentally friendly grass fed beef is prompting some farmers to adopt regenerative agriculture techniques. In the Midwest, farmers are slowly adopting the use of cover crops and no-till farming, which improves soil health and reduces the need for chemical fertilizers and herbicides, benefiting insects. This is why sourcing your foods from a local farmer is one of your best bets to ensure you're getting something wholesome while also supporting biodiversity on the planet.

And, you'll be supporting the small farms — not the mega-farming corporations — in your area. Ideally, support farmers who are using diverse cropping methods, such as planting of cover crops, raising animals on pasture and other methods of regenerative agriculture that protect beneficial insects. In addition, take steps to make your own backyard friendlier to your insect friends, by eliminating the use of pesticides and other chemicals and planting a diverse variety of native flowers and other plants.